Machine



H. KRIEGER.

LENS GRINDING MACHINE.

APPLICATION FILED FEB. I8. low

lutonlulAug. 1U, ISHJ.

3 SHEETS -S|IEEI l.

v v INVNTOR Hugo lfn'eger' A TTORNE VS H. KRIEGER.

LENS GRINDING MACHINE.

APPLICATION man FEB.18.1919.

Patented Au": 19, 1915).

3 SHEET -S|IEET 2.

lllll lL r 'lllil 4 lllfI/E/VTGH flag/(U1316178) Br Arm/rivers W/T/VESSES v/ .hrkz

H. KRIEGEH. LENS GRINDING MACHINE.

APILICA'HON FILED FEB-13. IJIU,

Patented Aug. 19, 1919.

3 SHEF-S SHEEI Li.

wk i w. W

HUGO KRIEGER, OF NEW YORK, N. Y.

LENS-GRINDING MACHINE.

Specification of Letters Patent.

Patented Aug. 19, 1919.

Application filed February 18. 1919. Serial No. 277.842.

To all whom it may concern:

Be it knownthat-I. HUGO KRIEGER, a citizen of Germany, having declared m intention to become a citizen of the Unite States, and a resident of the city of New York,

borough of Manhattan, in the county and State of New York, have invented a, new and Im roved Lens-Grinding Machine, of which t e following is a full, clear, and exact description.

The object of the invention is to provide a new and improved lens rindin machine more especially designed f or grin ing toric lenses and arranged to grind a large number of lenses at one time without requiring any attention on the part of an operator. Another object is to permit of making convenient and accurate adjustment for grindin lenses of different curvature. Another 0 ject is to permit convenient adjustment for grinding lenses of diflerent width.

With these and other objects in view, the invention consists of certain novel features of construction as hereinafter shown and described and then specifically pointed out in the claims.

A practical embodiment of the invention is represented in the accompan ing drawings forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the views.

Figure 1 is a front elevation of the improved lens grinding machine with parts shown in section,

Fig. 2 is a side elevation of the same with parts broken out; and

Fig. 3 is a plan view of the same with the dust cap omitted.

On a suitabl constructed base 10 are mounted spaced hearings 11in which is journaled a grinding wheel shaft 12 provided with a step ed pulley 13 connected by a belt with ot er machinery for imparting a rotary motion to the grinding wheel shaft 12. On the front end of the grinding wheel shaft 12 is removably secured a grinding wheel 14 on the peripheral face of which are cemented or otherwise temporarily secured a row of lenses 15 to be ground, it being understood that the under faces of the lenses l5 correspond to the peripheral face of the grmdin wheel 14, and by usin difrerent sized w eels 14 lenses with di erent inner curvatures can be ground as hereinafter more fully explained. The grindin wheel 14 is rovided with a split hub 1 fitting on to tie shaft 12 and provided with a clamping screw 18 for clampinglv fastening the hub ,17 to the shaft 12. By the arrangement described the grindin wheel 14 after the lenses are ground can o readily removed from the shaft 12 and replaced by another one provided with a new set of lenses to be ground at the next operation.

The outer faces of the lenses 15 are ngaged by a rinding or olishing tool 20 provided Wlt an upwar ly extending lug 21 fastened by a bolt 22 to the forward end of an arm 23 mounted to swin on a pivot 24 held in the upper end of a ever 25 rovlded with a pivot 26 journaled in a side 27 mounted to slide up and down in suitable guideways 28 attached to or formed on a standard 29 secured on the base 10. The lever pivot 26 has its axis adjustable up or down relative to the axis of the shaft 12 and the lever 25 rocks in a plane transverse to the plane of rotation of the inding wheel 14-. The lever 25 is rovide with a socket 30 concentric with the pivot 26 and mounted to turn on a-bearing 31 forming art of the slide 27. A wearing plate 32 1s interposed between the back of the socket 30 and the front face of the bearin 31 to ermit of replacing the wearing p ate 32 y a new one whenever such wearing plate is appreciably worn down. The forward reduced end of the pivot 26 is screwed or otherwise secured to the lever 25 and the rear end thereof is provided with nuts 33 to properly hold the lever in contact with the wearing plate 32-to insure proper rocking of the lever without danger of wabbling. It is understood that the large socket 30 and the bearing 31 tend to reduce the Wabbling motion to a minimum to insure accuracy in the grinding operation.

The lower end of the lever 25 is pivotally connected with a pitman 40 pivotally connected with. a wrist pin 41 held adjustable in a radial groove 42 formed in a crank disk 43 attached to a shaft 44 journaled in suitable bearings 45 and 46, of which the bearing 45 is mounted on the base 10 and the bearing 46 forms part of the left-hand bearing 11. is secured a stepped wheel 48 connected by a belt with other machinery for imparting a rotary motion to the shaft 44 which by the crankdisk 43 and the pitmen 40 imparts a rocking motion to the lever 25.

The slide 27 is provided with a rack 50 in mesh with a pinion 51 secured on a shaft 52 journaled in suitable bearings arranged on the standard 29. The shaft 52 is provided at its forward end with a polygonal portion 53 for the application of a wrench or other suitable tool to permit of turning the shaft 52 and with it the pinion 51 with a view to move the rack 50 and consequently the slide 27 up or down according to the direction in which the shaft 52 is turned. After the desired adjustment has been made the slide 27 is clamped in place in its guideway 28 by clamping bolt 54 for drawing the guideways 28 in clamping contact with the slide 27 (see Fig. 3). On the slide 27 is arranged an indicating line 60 adapted to register with a graduation 61 representing the corresponding diameters to which the lenses 15 on the grinding wheel 14 are ground. As illustrated in the drawings the grinding wheel is six inches and the range of the transverse curvature given to the lenses is from sizgto twelve inches and subbdivisions'. It-"-is understood that I do not limit ,myself to the sizes mentioned as machines eating the desired transverse curvature of the lenses to be ground at the time. Thus by the arrangement described the pivot 24 for the arm 23-is correspondinglyraised or lowered to insure a proper relation of the grind- 4 ing tool 20 with the wheel 14. As shown in Fig. 1, the machine. is set for grinding the lenses to a transverse curvature corresponding to 10.25. a

In order to limit the downward swinging movement of the arm 23 use is made of a lug arranged on the pivotal end of the arm 23 and adapted to abut against a screw 71 screwin in a split bearing 72 forming part of the ever 25. The split bearin 72 is adapted to be clamped to the screw 1 after the latter is adjusted by a suitable clamping screw 73. It will be noticed that by the arrangement described the arm 23 is limited in its downward swinging movement to pre vent further grinding or polishing of the lenses after the same have been ground to the desired degree. On the shaft 44 lever 25. A spring 86 is attached to the pawl 84 and bears against a pin 87 held on the lever 25, the spring 86 serving to firmly hold the pawl 84 in contact with the ratchet'wheel 83 to prevent turning of the knurled head 81 by the action of the spring 80. By the use of the ratchet wheel 83 and the pawl 84 the desired tension can be given to the spring 80 to cause the latter to bear on the pivot 24 and hence on the arm 23 to hold the tool 20 in contact with the lenses 15 and with the desired force. The lower end of the pawl 84 is provided with a handle 88 adapted to be pressed by the attendant whenever it is desired to dlsengage the pawl 84 from the ratchet wheel 83 to allow reducing the tension of the spring by turning the knurled head 81 in a reversedirection. The operation is as follows:

The lenses 15 of a given diameter at their 7 inner .faces are fastened to the peripheral surface of a wheel 14 of corresponding diameter .and this wheel is then'clamped to the shaft 12 by screwingup the clamping screw 18 on the split hub 17 of the wheel 14. The operator next adjusts the slide 27 up or down by correspondingly turnin the shaft 52 until the indicating line 60 registers with the mark on the graduation 61 indicating the transverse curvature to which the lenses are to be ground. The screw 71 is adjusted to limit the downward. swinging movement of the arm 23, that is, to stop further grinding of the grinding tool 20 on the lenses 15 after the same have been ground to the desired curvature.

It is understood that in starting the machine, the lug 70 is out of contact with the screw 71. The wheels 13 and 48 are now rotated tocause the inding tool 20 to succes sively engage the enses 15 held on the peripheral surface of the grinding wheel 14. and a sidewise oscillating movement is given to the arm 23 and consequently the grinding tool 20 by the action of the lever 25 is caused to oscillate by the pitman .40 con-- nected with the crank disk 43. it will be noticed that the tool 20 is held with the desired force in contact with the lenses 15. by the action of thetorsion spring 80, as above explained, and the grinding tool 20 is free to rock on the arm 23 owing to the pivotal is set and started for grinding the lenses to a desired curvature the machine requires no further attention and hence an operator may do other Work or attend to a number of machines. In practice it usually takes about four hours for grinding a set of lenses.

Having thus described my invention, I claim as new and desire to secure by Letters Patent j 1. In a grinding machine for grinding toric lenses, a revoluble lens carrying wheel adapted to carry on its peripheral face a row of lenses to be ground, a non-rotatable grindin tool on top of the said wheel and arrange in operative relation to the said lenses, n arm on which the said grinding tool is pivoted, a lever on which the said arm is mounted to swing up and down, a slide mounted to slide up and down and on Which the said lever is mounted to swing in a plane at a right angle to the plane of the said lens carrying wheel, and a rack and pinion mechanism connected with the said slide to adjust the latter up or down, the said lever being in zero position whenever the axes of the grinding wheel and the lever are in the same horizontal lane.

'2. In a grindin machine for grindin toric lenses, a revoluble lens carrying whee I adapted to carry on its peripheral face a toric lenses, a revo row of lenses to be ground, a non-rotatable grinding tool arranged in operative relation with the top of the said wheel to grind the said lenses, an arm on which the said tool is pivoted, a lever on which the said arm is mounted to swing up and down, the said lever having a large socket, a slide mounted to slide up and down and provided with a bearing engaged by thesaid socket for the said lever to rock in a lane at a right angle to the plane of the said lens carrying wheel, and a rack and pinion mechanism connected with the said slide to adjust the latter up or down.

3. In a grindin machine for grindin Fable lens carrying whee adapted to carry on its peripheral face a row of lenses to be ground, a non-rotatable grinding tool arranged in operative relation with the top of the said wheel to grind the said lenses, an arm on which the said tool is pivoted, a lever on which the said arm is mounted to swing up and down, the said lever having a large socket, a slide mounted to slide up and down and provided with a bearing en aging the said socket for the said lever to roe 1n a plane at a right angle to the plane of the said lens carrying wheel, a rack and pinion mechanism connected with the said slide to adjust the latter up or down, a fixed graduation, and a pointer on the said slide indicating on the said graduation, the said lever being in zero position when the axes of the grinding wheels and the lever are in the same horizontal plane.

4. In a grindin machine for grindin toric lenses, a revo uble lens carrying whee adapted to carry on its eripheral face a row of lenses to be ground, a non-rotatable grinding tool arranged in operative relation with the top of the said wheel to grind the said lenses, an arm on which the said tool is pivoted, a lever on which the said arm is mounted to swing up and down, the said lever having a large socket, a-slide mounted to slide up and down and provided with a bearing engaging the said socket for the said lens to rock in a plane at a right angle to the plane of the said lens carrying wheel, a rack and pinion mechanism connected with the said slide to adjust the latter up or down, and actuating means for rotating the said lens carrying wheel and rocking the said lever in unison.

5. A grinding machine for grindin toric lenses, comprising a revoluble wheel a apted to carry on its peripheral face a row of lenses, an arm carrying a grinding tool ar ranged in operative relation to the said lenses, a lever carrying a pivot for the said arm to allow the latter to swing up and down, the fulcrum of the lever being adjustable relative to the axis of the said wheel, means imparting a rocking motion to the said lever, a torsion spring attached at one end to the said arm pivot, a head mounted to turn and engaged by the other end of the torsion s ring, a ratchet wheel on the said head, an a pawl engaging the said ratchet wheel.

6. A grinding machine for grindin toric lenses, comprising a revoluble wheel a apted to carry on its peripheral face a row of lenses, an arm carrying a grinding tool arranged in operative relation to" the said lenses, a lever carrying a pivot for the said arm to allow the latter to swing up and down, the fulcrum of the lever being ad'ustable relative to the axis of the said w eel, means imparting a rocking motion to the said lever, a torsion spring attached at one end to the said arm pivot, a head mounted to turn and engaged by the other end of the torsion spring, a ratchet wheel on the-said head, a pawl engaging the said ratchet heel, and a stop limlting the swinging movement of the said arm.

7. In a grinding machine for grindin toric lenses, a revoluble lens carrying whee adapted to carry on its peripheral face a row of lenses to be ground, a non-rotatable grinding tool on top of the said wheel and arranged in operative, relation to the said lenses, an arm on which the said grinding tool is pivoted, a lever on which the said arm is mounted to swing up and down, a slide mounted to slide up and down and on which the said lever is mounted to swing in aplane at a right angle to the plane of the said lens carrying wheel, and manually controlled means connected with the said slide to adjust the latter up or down, the said 10 lever being in zero position whenever the axes of the grinding wheel and the lever are in the same horizontal plane.

HUGO KRIEGER. 

